Conventional devices for dismounting an electrical component, such as a ball grid array (“BGA”), chip scale package (“CSP”) or a plastic leaded chip carrier (“PLCC”), by melting the solder of a soldered connection with hot air and then removing the component from a printed wiring or circuit board are known.
During the desoldering process, the related art discloses that a spring assists in the removal of a component once a suction cup is attached. The user can turn the adjustment knob to apply a spring loading by compressing the spring. The vacuum pickup tube and the suction cup will exert sufficient suction to remain affixed to the component. When the solder melts the spring will automatically lift the component free of the substrate.
However, in the prior art designs, the structure does not allow the user to confirm when the solder is sufficiently melted so that the component can be safely detached. In many cases, a large number of electronic components are densely placed on the printed wiring or circuit board substrate. Therefore, surrounding electronic components located next to and around the electronic component to be lifted by the heating device often block the line of sight of the operator who is trying to remove a component. In some cases, the operator may not notice the displacement or lifting of the component after the solder has been melted allowing the electronic component to be separated from the substrate. If the operator does not notice the upward displacement of the electronic component, the operator may continue to apply heat to the substrate and the surrounding electronic components, and the substrate and surrounding electronic components may be thermally damaged. Alternatively, the operator may at times attempt to lift the heating device upward to confirm whether the solder has been sufficiently melted, before the component can be safely removed. If the melting of the solder is insufficient, the lands of the circuit board may be damaged. For this reason, a failure such as overheating of the component due to a long period of application of hot air, or peeling off the land of the substrate when the user lifts the handle before the solder is completely melted may occur.